Making sopython-site usable by others

[Ffisegydd]

Part of having sopython-site open source is that, eventually, other users should be able to take it and use it to build their own community sites with it.

As such, when developing parts of the site we should try to keep this in mind, and make it easy to tinker/replace key parts. @davidism made this part clear in a comment on Trello:

sopython is currently geared completely towards the python chat, I'd want to expose more configuration/branding/theming if we were to suggest it to others.